I'm using calibre. I have my iphone plugged into my laptop, and I pick a book. Then I click send to device. Then I get the error message, cannot send, no device is connected.

Why is this happening, and how can I download e-books, or upload, not sure about the proper terminology, to my iphone. I currently don't have internet on my iphone, so I can't send the books to my iphone, through e-mail.